I really don't think anyone should have a problem with the Cadet Program. A company like Qantas should have a valid way to compare different strategies for crewing an aircraft. Keg has touched on an important issue regarding lifestyle and culture.
At my employer here Stateside, we have furloughed pilots from various major airlines and they have distinctively different personalities in the cockpit, largely based upon the corporate culture of their old employer.
This has sometimes proved quite difficult in the training environment and even in the way that they communicate with maintenance and use their skills in customer service.
The problems that we see very rarely have to do with physical handling of the aircraft.
I know two cadets that were sons of QF crew at Sydney Tech. They had excellent scholastics and were obviously aware of the lifestyle choice they were embarking on. That's half the equation right there!